Metal derivatives of amino methylene aldehydes



, dergo the reaction. In

Patented Apr. 7, 1942 UNITED STATES PATENT OFFICE Adrianna Johannes van Andreas van asdgnors to San Francisco,

METAL DERIVA METHYLENE Johannes Netherlands, Company, of Delaware Drawing. 1939, Serial No.

plication September 5, 1939, Serial No.

February 22, 1938 In the Netherlands TIVES OF AMINO ALDEHYDES Peski, Nicolaas Max and Melaen, Amsterdam, Shell Development Calif a corporation rlginal application February 11,

255,814. Divld ed and this all- 6 Claiml. (Cl. 260-429) The present invention relates to amino methylene aldehydes of the general formula Still a further object is toprovide a process for of the above class 1 methylene aldehydes and the metal derivat the preparation thereof.

of amino Amino methylene aldehydes of the above general formula, we in general, by reacting containing at have found, may be prepared, ammonia or an amine least one replaceable nitrogenbond hydrogen atom with a dialdehyde of the general formula.

The reaction, although it proceeds at quite different rates depending on the type and character of the amino compound employed and upon the character of the substituen t designated by R2,

takes place, in general, readily with good yields and is, we have dialdehydes of the found, quite general structure characteristic of II. Dialdehydes having carbonyl groups separated by more than one carbon atom,

for example, order for the reaction to do not untake place it is furthermore necessary that the carbon atom connecting the have at least one two carbonyl groups hydrogen atom attached thereto. The reaction apparently proceeds according to the following mechanism:

product and to some exends upon the charives acter of the amino-compound employed and the substituent designated in the general formula by R2. B: may, in general, be a hydrogen atom or any organic radical attached through a carbon 5 groups; for example, by

atom. For instance, Ra may be an aliphatic radical such as methyl, butyl, butenyl, pentyl, clopentenyl, cyclohexyl, cyclohexadienyl, etc. or may be of aromatic character, such as for instance phenyl, p-xylyl, benzyl, p-tertiary butyl phenyl, cinnamyl, beta phenyl ethyl, etc. Particular properties may also be imparted to the products by employing compounds in which the more substituted employing dialdehydes various chloro, bromo, amino, hydroxy, alkoxy, thiol, etc., substituted radicals. AS the weight of the R2 substituent increases, the rate of reaction is somewhat decreased and the R: group contains one or containing the 0 product in general tends to become soluble in amines is their monia and primary amines non-polar solvents.

The above-described applicable dialdehydes may be reacted, in general, with any amino compound containing at least one replaceable aminohydrogen atom. As examples of amino-compounds which may be employed may be mentioned, besides ammonia, for example, the primary and secondary alkyl amines, alkanolamines, cycloparafiin amines, benzyl amines, aniline, piperidine, allyl amines, p-toluidine, alkyl diamines, aliphatic amino acids, as well as aminocompounds in which one or two of the amino hydrogen atoms of ammonia have been replaced by substituted radicals, such as and the like. The character of the amino compound employed, however, aifects to a considerable degree the properties of the product and the rate of reaction.

While in general any of the above-mentioned amino compounds can be made to react with alaldehydes of the general Formula II, those of secondary character react to give products of relatively restricted utility. The compounds of the general Formula secondary amines may find application as intermediates in chemical synthesis, but are incapable of forming the valuable and useful metal derivatives described below.

Other disadvantages of the use of secondary lower reaction rate. While amtend, in general, to

ethyl, propyl, lsopropyl. pentenyl, cyclopentyl, cy-

I, for example, derived from i react smoothly with For these reasons, the the general Formula good yields, Secondary mines, with the exception of the few lower alihatic secondary amines, react rather slowly.

products corresponding to I derived from secondary mines represent a less important embodiment f our invention. or the amino methylene aldehydes of the structure I, those prepared by rephatic character are,

cting amino-compounds oi predominantly aliin general, the most suited s intermediates in organic synthesis, and are therefore preferred.

While we may prepare amino methylene aldehydes of the general structure I, according to the above-described better method for pounds.

process, we have found a much the preparation of these com- According to the preferred process of ur invention, the amino methylene aldehydes are prepared by reacting an amino-compound,

such as described above, the general Formula II,

not with a dialdehyde of onceivably derived therefrom by reaction with 11 alcohol. Thus, for example, we preferably react one of the above-described amino compounds with a compound of one of the following eneral structures:

11 H on, III 0: -n

Ra0 OR: w H- -c H B:- R; i

H on. V RiO-( 3=O( JH I l: R:

H a v1 o=co= s'oa,

wherein R: has the same significance as the bove and R3 represents an aliphatic radical such as for instance methyl, ethyl, propyl, etc.

III, IV, V, and be considered enol ether acetals and enol ethers,

Compounds of the above general structures VI as will be readily seen, may as the mono-acetals, di-acetals, respectively,

f the dialdehydes of the generalFormula If.

They are conceivably, although not necessarily,

erived from the above described dialdehydes by reaction with an alcohol (RaOH) according to the schemes:

The preparation of the present amino methyland practical but with a compound ene aldehydes by reacting an amino compound with these acetals, enol ethers or enol ether acetals conceivably derived from the corresponding 1,3 'dialdehyde, according to the preferred process of the invention, is a much more simple method, and in general eliminates the necessity of preparing and isolating the 1,3 dialdehydes per se, many of which can only be prepared with relatively poor yields and with considerable difiiculty.

' The reactions involved when reacting amino compounds with the above described derivatives of 1,3 dialdehydes may be illustrated by the following examples:

The reaction of the amino compound with dialdehydes of the general structure II, or according to the preferred embodiment of the process of the invention, with an acetal, enol ether or enol ether acetal of the 1,3 dialdehyde, does not require particular precautions, but takes place, in general, at a temperature or below by cooling. After the major portion of the reaction has taken place the reaction mixture may be advantageously allowed to stand for several hour at normal temperatures to insure completion of the reaction. In some cases where less reactive reagents are employed a moderate heating, such as for instance 30-50 C., may be advantageously employed to initiate and, if desired, maintain a satisfactory reaction rate.

When preparing amino methylene aldehydes according to the preferred embodiment of the invention, (i. e., by using an acetal, enol ether above equations, it isnecessary that enough water should be present in the reaction mixture to form a molecule of alcohol from each of the OR3 groups present. Since the products, pergms. of ethyl aminomethylene propionaldehyde ticularly the lower members and those in which the R1 and/or R2 groups contain substituted hydrophlllic. groups, are generally. water-soluble and their recovery in the anhydrous state from water solutions is in some cases somewhat diflla cult, it is, in general, advisable in most cases to avoid the presence of any water above that required in the reaction.

The reaction may, if desired, be executed in the presence of an inert solvent or diluent. For this purpose any inert liquid material, preferably a solvent for one or both of the reactants, may be used. As examples of suitable diluents may be mentioned diethyl ether, benzene, chloroform, and the like. The normally liquid paraffin hydrocarbons such as hexane are especially suited.

The following examples which, it is to be understood, are not -to be considered as limiting the invention in any manne are given to illustrate the preparation of a few of the simpler amino methylene aldehydes according to the preferred process of the invention.

Example I 50 gms. of ethyl amine was added slowly to 174 gms. of ethoxy-methylene acetaldehyde diethyl acetal and 54 gms. of water while stirring and cooling with ice. The reaction mixture was allowed to stand over night and was then subjected to a fractional distillation under vacuum. A good yield of a product having the formula:

was obtained. This compound is a clear, stable, water-soluble acid-reacting liquid, boiling at 110-1 12 C. at 9 mm. pressure.

Example II 37 gms. of methyl amine were conducted ingaseous form into a mixture of 174 gms. of ethoxy methylene acetaldehyde diethyl acetal and 54 gms. of water while stirring and cooling with ice. The reaction mixture was allowed to stand for 24 hours and then subjected'to a fractional distillation under vacuum. A product having the formula CHa-III-(|3=CC=O HHHH was obtained in a yield of 44 gms. corresponding to 52% of the theory. This compound is an acid-reacting, clear, stable, water-soluble liquid boiling at 73'75 C. at 0.1 mm. pressure.

Example IV 37.6 gms. of ethoxy methylene-2 propionaldehyde-l diethyl acetal were mixed with 10.8 gms.

whereupon the mixture was of water and 9.0 gms. of ethyl amine and the 7 mixture was shaken during 48 hours. The reaction product was then subjected to a fractional distillation .under vacuum, which yielded 17 boiling at ill-112 C. under 0.2 mm. pressure.

The other amino aldehydes of the general structure I may also be prepared in a similar manner. The present amino methylene aldehydes are distinctly acid, and in many cases very strongly acidic in character. This is due to the ability of all the amino aldehydes of the general Formula I prepared by using a primary amine or ammonia (i. e., in which R1 in at least one case is hydrogen) to tautomerize, at least partially, into the strongly acidic enol form.

R|-NC=CC=0 (VII) (VIII) We have found that these amino methylene aldehydes of the structures VII and/or VIII may be readily converted into new and valuable metal derivatives by reacting with suitable salts of metals. In general, these amino methylene aldehydes may be reacted with salts of any of the metals of atomic number greater than 21. Of the available metal salts, those in which the metal atom exists with a valence of from two to four, such as for instance Ti Mn++, Fe z s Hg++ Pb++ etc., are in general preferred. Of the available salts of the metals we may employ for example the halides, sulfates, nitrates, carbonates, chlorates, perchlorates, salts of organic acids and the like. We prefer in general salts having an appreciable solubility in water and/or alcohol. Examples of suitable metal salts are SbCla, CdCla, CoCla, CoCls, CuCh-2NH4C1-2Hz0, CuCla, FeClz, FeCla, MnCla, MnCh, NiCh, SnClz, SnCh, TiCla, TlCls, TiCli, V014, ZnCh, AsFa, CrBrs, CuBrz, FeBrz, FeBrs, VBra, Co(Cl04)2, Cu(ClOa)2, Pb(Cl0a)z, Ni(C10a) z, AgClO4, CdCOa, Cr(NH4), (SO02, Cl'z(SO4)3, MIl(NO3)2, 211504, antimony lactate, basic iron acetate, iron malate, basic lead acetate, mercuric acetate, silver salicylate, zinc acetate, zinc benzoate, zinc citrate, and the like.

The metal derivatives prepared by the reaction of the present amino methylene aldehydes with metal salts vary in structure and properties depending upon the number of the anions of the metal salt displaced by the amino methylene aldehyde. For example, when a di-valent metal salt such as COClz, NiClz, Cu(C2Ha02)2, or the like is reacted with an excess of an amino methylene aldehyde, compounds of the following structures are obtained:

Certain properties of the metal derivatives indicate that the metal atom is bound by secondary valence forces to the nitrogen atoms. These secondary valence bonds, probably present, are indicated in the above formulae by broken lines.

The reaction of the amino methylene aldehyde with the metal salt to form the metal derivative may be simply brought about by mixing a. solution of the metal salt with a solution of the amino methylene aldehyde or alkali salt thereof at ordinary temperature. The metal derivative separates out in general as an oily layer which usually crystallizes upon standing, or separates directly as a precipitate, depending upon the metal used and the character of the amino'methylene aldehyde employed.

The majority of the metal derivatives may be prepared, for example, by adding a solution of the metal salt to a solution of the amino methylene aldehyde in an equimolar quantity of dilute alkali. The product which, in the case of most of the higher homologues, separates as a granular precipitate may be washed and dried. In genera], to free the product from any occluded metal oxides or hydroxides, it may be dissolved in a suitable organic solvent, filtered and recovered pure from the solvent by precipitation therefrom or by evaporation of the solvent.

Many of the lower homologues, i. e. metal derivatives in which R1, R2 and/or R4 are hydrogen atoms, or lower molecular weight radicals, sepif an. a...

143 0. at 0.1 mm.)

IHI 4H0 (MO-148 C. at 0.12 mm.)

It is usually advantageous in the recovery and purification of such lower homologues as .the

- above to avoid unnecessary quantities of water arate as liquids which, in some cases, are difflcult to crystallize. For instance, the following metal derivatives are liquids which may be distilled. Their respective boiling points are given in the parentheses.

Cu C-H 3=N 1|-I=QH H 13H: CH:

(co-95 C. at 0.2 mm.)

(108 C. at 0.15 mm.)

lite.

(MO-150 C. at 0.12 mm.)

H H t4. 0J1 a no Cu c-n during the reaction. Thus, for example, a concentrated aqueous solution of copper acetate may be added to a solution of the amino methylene aldehydes in acetone, alcohol or the like. By choosing metal salts having an appreciable solubility in alcohol, the reaction may also be advantageously executed in an anhydrous alcoholic medium. This is illustrated by the following example.

Example V A quantity of ethyl amino methylene acetaldehyde was dissolved in an absolute alcohol solution of an equimolar quantity of sodium ethylate. The metal derivative was formed upon addition to this solution of an absolute alcohol solution of cupric chloride. The metal derivative was puriflecl by fractional distillation under high vacuum (boiling point 108 C. at 0.15 mm. pressure).

Aside from the metal derivatives of the above described type wherein all the principal valences of the metal atom are satisfied by radicals derived from the amino methylene aldehydes, metal derivatives may be prepared in which only a fraction of the anions of the metal salt has been substituted by the amino methylene aldehyde. Thus, for example, by proper choice of metal salts and proportions, compounds of the type illustrated by the compounds (CgHgOz) H A Ala Hi may be prepared.

Compounds of this class, wherein one or more of the principal valences of the metal is attached to a salt-forming anion such as for instance an acetate group, nitrate group, chloride, bromide, iodide or the like, are very desirable for certain uses, due to their greater solubility and in general greater reactivity.

The amino methylene aldehydes may also be reacted with metal salts in which only a fraction (A) :M(R) 1! wherein M represents an atom or the metal, A represents a salt-forming anion such as described above, R represents a hydrocarbon or substituted hydrocarbon radical such as for instance methyl, ethyl, isoamyl, phenyl, benzyl, isobutenyl, p-methoxy phenyl, betanaphthyl, p-tolyl, p-xylyl, chloroethyl, cyclohexyl, amino phenyl or the like connected to the metal atom through a carbon atom, :1: represents a positive whole number, and y represents a positive whole number equal to the valences oi the metal atom minus 2:. As examples of suitable metal salts of this type may be mentioned trimethyl antimony dilactate, amino phenyl mercuric acetate, diisoamyl tin dibromide, dibenzyl tin diacetate, dibenzyl tin dichloride, diethyl-n-propyl tin chloride, diphenyl tin hydroxy chloride, lead diphenyl dichloride, lead diphenyl dibromide, and the like. By employing salts of this type in which at least one hydrocarbon or substituted hydrocarbon radical is attached to the metal atom through a carbon atom, metal derivatives such as H C2115 H l-O o- H I C CsHs i535 C011:

and the like may be formed.

Metal derivatives of this type having organic radicals attached to the metal atom by a metalcarbon linkage differ, in general, considerably in physical and chemical properties from the metal derivatives described above in which the organic radicals are all attached to the metal atom through oxygen. These metal derivatives for example, have, in general, appreciably higher vapor pressures, lower boiling points, greater solubilities in non-polar solvents, and decreased solubilities in aqueous media. They are, for example, excellent as a means for introducing various metals in a reactive form in solution in various organic and non-polar solvents.

The amino methylene aldehydes of the present invention are valuable as intermediates for the preparation of numerous compounds. Aside from their use as intermediates in the preparation of the metal-organic compounds described above, they may find application as intermediates in the preparation of many organic compounds which are diflicult or as yet impossible to prepare by other methods.

The metal derivatives of the present amino methylene aldehydes may find application, for example, in the preparation of insecticidal, fungicidal, and/or bactericidal compositions, in preparations for the proofing of textiles, furs and cellulosic materials against moths, beetles, termites and other pests, in the preparation of pharmaceuticals, in fuels for internal combustion engines, in the treatment of plant seeds, and the like.

This application is a division of our copending application. Serial No. 255,874, filed February 11, 1939, Patent No. 2,228,039.

We have in the foregoing described our invention in some detail and have illustrated the preparation of several typical representative examples o! the broader class of amino methylene aldehydes and metal derivatives to which our invention relates. It is to be understood, however, that while we have described, illustrated and explained the various aspects of the invention according to the best of our present knowledge, our invention is not to be limited to the specific i1- lustrative examples, nor by the soundness or accuracy of any theories, structural formulae or the like.

We claim as our invention:

1. A metal derivative of an amino methylene aldehyde containing the structure 11 R1 wherein R1 and R2 each represent a substituent of the group consisting of the hydrogen atom, the hydrocarbon radicals, and the substituted hydro carbon radicals wherein the substituent is a member of the group consisting of the chlorine and bromine atoms and the amino, hydroxy, alkoxy and thiol radicals, M represents an atom of a heavy metal and R3 represents a hydrocarbon radical.

2. A metal derivative of an amino methylene aldehyde containing the structure the group consisting of the hydrocarbon radicals and salt-forming anions.

3. A metal derivative oi. an amino methylene aldehyde containing the structure H R1 wherein R1 and R2 each represent a substituent of the group consisting of the hydrogen atom, the hydrocarbon radicals, and the substituted hydrocarbon radicals wherein the substituent is a member of the group consisting of the chlorine and bromine atoms and the amino, hydroxy, alkoxy and thiol radicals, M represents an atom of a heavy metal, and R represents a salt-forming anion.

4. A metal derivative of an amino methylene aldehyde containing the structure I RIJX wherein M is a heavy metal, R1 and R2 each represent a substituent oi the group consisting of the hydrogen atom, the hydrocarbon radicals, and the substituted hydrocarbon radicals wherein the substituent is a member of the group consisting of the chlorine and bromine atoms and the amino, hydroxy, alkoxy and thiol radicals, R represents a substituent of the group consisting 01' the hydrocarbon radicals and salt-torming anions, X represents a positive whole numher, and 1 is equal numerically to the valence of the metal minus X.

6. A metal derivative of an amino methylene aldehyde wherein a heavy metal is directly attached to an oxygen atom which is joined to a carbon atom attached by an olefinic bond to a carbon atom to which an amino methylene group is directly attached.

ADRIANUS JOHANNES VAN PESKI. NICOLAAS MAX. JOHANNES ANDREAS VAN MELSEN. 

